Types of childhood adversity and the ACE score

"Adverse childhood experiences," or ACEs, is a research term. It names a set of hard things that can happen to a child before age 18.¹ The list began with a study in the 1990s and has grown since then.

This page describes the main types of childhood adversity in general terms, without graphic detail. It also explains what an ACE score is and what it can and cannot tell you. Reading a list like this can bring up memories. Go at your own pace, and take a break whenever you need one.

The original ACE categories

The CDC–Kaiser Permanente ACE Study ran from 1995 to 1997. More than 17,000 adults in Southern California answered private questions about their childhoods during routine checkups.² The researchers grouped hard experiences into three kinds. The table shows how often each was reported in that group of adults.²

Neglect was asked about only in the second part of the study. Almost two-thirds of these adults reported at least one ACE. About 1 in 8 reported four or more.² Most of the people in early ACE research were white and middle class, so the numbers may differ in other groups.³

Abuse

The CDC describes four forms of child abuse and neglect by a parent or caregiver:⁹

• Physical abuse means using force on purpose in a way that can injure a child.
• Sexual abuse means involving a child in any sexual act or contact.
• Emotional abuse means behavior that harms a child's sense of worth or emotional well-being. Examples include name-calling, shaming, rejecting a child or withholding love.
• Neglect is the fourth form, described below.

Emotional abuse can be hard to name, because it leaves no marks. In a recent national survey it was the most common ACE, reported by about 1 in 3 U.S. adults.¹⁰

Neglect

Neglect means a child's basic needs are not met. These needs include food, a safe place to live, clothing, health care, schooling and emotional support.⁹ Physical neglect is about the body: being hungry, dirty or without care when sick. Emotional neglect is about feeling unloved, unseen or not important to anyone in the family.

Neglect is about what was missing, so some people may not recognize it until much later.

Household challenges

These are problems in the adults around a child. They include violence between adults at home, a parent's alcohol or drug problem, a parent's serious mental illness, parents separating, and a household member going to jail or prison.² The CDC also lists a family member attempting or dying by suicide.¹

None of these mean that a parent did not love their child. A parent can be ill, struggling or absent and still care deeply. But a child in these homes may live with fear, chaos or loss.

Hardships the original list left out

The first ACE list focused on what happened inside the home. Later research has asked about the wider world a child grows up in.

• Poverty, hunger and unstable housing. The CDC names food insecurity, homelessness and unstable housing as experiences that can harm children.¹ In one national survey of young people, adding low family socioeconomic status, such as low income, to the ACE list improved the prediction of physical health problems.⁴
• Violence in the community. Seeing violence in the neighborhood is now on the CDC's list.¹ The World Health Organization's ACE questionnaire also asks about community violence and about living through war and other group violence.⁵
• Bullying and being left out by peers. In the same survey of young people, adding peer bullying, peer rejection and community violence improved the prediction of mental health symptoms.⁴ The WHO questionnaire also includes violence from peers.⁵
• Discrimination, unsafe neighborhoods and foster care. A Philadelphia study of about 1,800 adults added these "expanded" ACEs. About 1 in 7 people had only expanded ACEs. Their hardships would have been missed by the original list.³
• Losing a parent. The death of a parent in childhood is also studied as an adversity. A 2026 review linked it with a higher risk of dementia late in life.¹¹

Other hard events can matter too, such as serious illness, disasters or the death of a brother or sister. A list cannot capture every childhood.

What an ACE score is

An ACE score is a count. You get one point for each type of adversity you experienced before age 18. On the original 10-item list, scores run from 0 to 10.² Each type counts once, no matter how many times it happened.

The ACE score was made for research. It helps scientists compare large groups of people and track how common ACEs are. In the ACE Study, about 36% of adults scored 0, and about 12.5% scored 4 or more.² Many state health surveys now include a version of the ACE questions.²

What an ACE score cannot tell you

An ACE score is simple, and that is both its strength and its weakness. Experts point out several limits:⁶

• It is not a diagnosis. It does not tell you whether you have PTSD, depression or any other condition.
• Every item counts the same. A parent's divorce and years of sexual abuse each count as one point. But they are very different experiences.
• It misses severity, frequency and timing. One frightening event and years of harm look the same on a yes-or-no list. So do hardships at age 3 and at age 16.
• It leaves out what helped. The score does not count the grandparent, teacher, coach or neighbor who made you feel safe.
• It can sound like a sentence. Experts warn that simple scores risk sounding fixed and final. They can also carry stigma.⁶

Support matters a great deal. Harvard's Center on the Developing Child explains that the same hard event can affect children very differently. A frightening event with a caring adult nearby is more likely to be a stress the child can recover from. Long-lasting hardship without that support is more likely to become toxic stress.¹²

A poor predictor for one person

ACE scores are good at showing that, on average, groups with more ACEs have more health problems. They are poor at predicting what will happen to an individual.

• One study followed about 2,000 young people in the U.K. from birth to age 18 and about 900 people in New Zealand to age 45. ACE scores predicted later health problems only a little better than chance.⁷
• A re-analysis of the original ACE Study data reached the same conclusion. Many people with high scores did not develop the health problems studied. Many people with low scores did.⁸

So if your score is high, it does not mean illness is coming. If your score is low, it does not mean your pain is small.

If you are counting your own ACEs

You may be adding up your own score as you read. That is natural. Here are a few things to keep in mind:

• Notice how you feel. You may feel sad, angry, numb or shaky. If you feel overwhelmed, stop and try grounding or slow breathing.
• Your story is bigger than a number. Think also about the people and places that helped you. See Protective factors and resilience.
• You choose what to share. You do not have to tell anyone your score or your story until you are ready.
• MindCheck has an optional set of ACE questions for adults. You can skip any of them. Your answers are never a diagnosis. See WhySigh MindCheck.

Common questions

When to get help

Think about talking with a doctor, counselor or therapist if memories of childhood are affecting your sleep, mood, relationships or work. Also reach out if you use alcohol or drugs to cope, or if you feel numb or on guard much of the time. These can be signs of PTSD, depression or other conditions that can be treated. See Treatment.

Education only. This page is general information written from the sources listed. It is not medical, legal or financial advice and does not replace a doctor, therapist or lawyer who knows your situation. How we write and check pages.